42 THE SUGAR-BEET WIREWORM. 



In one instance, when the female in a cell had been dug up she came 

 m contact wdtli the male. The latter attempted copulation, but 

 unsuccessfully. 



OVIPOSITION. 



On April 9, 1912, the first eggs were deposited. These were laid 

 in a A"ial which contained several females in wliicli the development 

 of the eggs was more advanced. These eggs were scattered through- 

 out the soil. 



In only one instance was a female noted in oviposition, and that 

 was untler unnatural circumstances. Several gravid females had 

 been placed in a glass, on the bottom of which was about half an inch 

 of very compact soil. This glass was placed in the dark room for 

 several hours, and when observed again one female was attempting 

 oviposition between the soil and the glass. The beetle thrust her 

 ovij)ositor doA\Ti several times, and finally the egg was placed in the 

 bottom of the hole made by the ovipositor. The ovipositor was 

 then withdrawn slowly and then thrust back part w^a}' several tunes 

 as if the beetle were trying to cover the egg. The entire operation 

 took but a very short time. 



When the soil in the cages was broken up and examined for eggs 

 it was seen that oviposition under natural conditions must be quite 

 similar to that observed, as eggs were found at intervals under the 

 channel made by the digging female. 



By the latter part of May the females became very scarce, as they 

 live but a short tune after laj'ing their eggs. The males for the 

 greater part died during about the middle of the period of OAa})ositioii. 



Approximate Length of the Life Cycle. 



Considering the length of the egg stage as one month and the 

 length of the pupal stage as the same, these, added to the length of 

 the life of the adult, will give from five to eight months. If, as has 

 been stated before, the larval stage lasts for over three years, it is 

 seen that the length of the life cycle from egg to egg would be four 

 years. 



seasonal history. 



Beetles from Emergence to Hibernation. 



The life of the adult, from emergence, through hibernation, until 

 their appearance after hibernation, is governed to a great extent by 

 conditions over which the beetles themselves have no control. The 

 greater j)art of the l)eetles emerge from the pupse about the middle 

 of September. The beets are plowed up for the most part during 

 September and October, so the insect is in danger of being disturbed 

 either during the pupal stage or soou after it has changed to the 



